Enhanced Visible-Light Photocatalytic Performance of SAPO-5-Based g-C(3)N(4) Composite for Rhodamine B (RhB) Degradation

Novel visible-light responded aluminosilicophosphate-5 (SAPO-5)/g-C(3)N(4) composite has been easily constructed by thermal polymerization for the mixture of SAPO-5, NH(4)Cl, and dicyandiamide. The photocatalytic activity of SAPO-5/g-C(3)N(4) is evaluated by degrading RhB (30 mg/L) under visible light illumination (λ > 420 nm). The effects of SAPO-5 incorporation proportion and initial RhB concentration on the photocatalytic performance have been discussed in detail. The optimized SAPO-5/g-C(3)N(4) composite shows promising degradation efficiency which is 40.6% higher than that of pure g-C(3)N(4). The degradation rate improves from 0.007 min(−1) to 0.022 min(−1), which is a comparable photocatalytic performance compared with other g-C(3)N(4)-based heterojunctions for dye degradation. The migration of photo-induced electrons from g-C(3)N(4) to the Al site of SAPO-5 should promote the photo-induced electron-hole pairs separation rate of g-C(3)N(4) efficiently. Furthermore, the redox reactions for RhB degradation occur on the photo-induced holes in the g-C(3)N(4) and Al sites in SAPO-5, respectively. This achievement not only improves the photocatalytic activity of g-C(3)N(4) efficiently, but also broadens the application of SAPOs in the photocatalytic field.